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排序方式: 共有1232条查询结果,搜索用时 218 毫秒
731.
Environmental Science and Pollution Research - Traditional Chinese medicines (TCMs) are widely used to treat various diseases in China and some countries, and TCM products are becoming increasingly...  相似文献   
732.
Environmental Geochemistry and Health - Soil Pb concentrations at urban agriculture sites (UAS) commonly exceed recommended safe levels. There is a lack of evidence regarding uptake of Pb by...  相似文献   
733.
Li G  Sang N  Guo D 《Chemosphere》2006,65(6):1058-1063
The effects of the Xingou landfill leachate on levels of thiobarbituric acid reactive substances (TBARS) and the activities of Cu, Zn-superoxide dismutase (Cu, Zn-SOD), Se-dependent glutathione peroxidase (Se-dependent GPx) and catalase (CAT) were investigated in hearts, kidneys and spleens of Kunming albino mice of both sexes. Exposure to leachate caused significant increases of TBARS levels in the organs tested from mice of both sexes. For hearts, Cu, Zn-SOD, Se-dependent GPx and CAT activities were significantly increased at high concentrations for male mice, but the activities of these antioxidant enzymes were significantly increased at low concentration and decreased at high concentrations for female mice. For kidneys, Cu, Zn-SOD and Se-dependent GPx activities were significantly increased at high concentrations for male mice, but the activities were significantly increased at low concentrations and the ratio of increase was reduced with the increasing of concentration for female mice; CAT activities remained unchanged for male mice and were significantly increased at all concentrations tested for female mice. For spleens, Cu, Zn-SOD and Se-dependent GPx activities were significantly increased at high concentrations for male mice, but the activities were significantly increased at low concentrations and decreased at high concentrations for female mice; CAT activities remained unchanged for male mice and were significantly increased at high concentrations for female mice. The results suggest that leachate exposure can cause oxidative damage on hearts, kidneys and spleens of mice, and there were sex difference and organ difference in the response of antioxidant status.  相似文献   
734.
电催化氧化处理焦化废水静态实验研究   总被引:1,自引:0,他引:1  
用电催化氧化处理焦化废水,研究了电压、电流密度、电解时间和电解质浓度对COD去除效果的影响,并通过多因素正交试验确定了该工艺最佳操作参数:电压为20 V,电流密度为94 mA/cm2,电解时间2.5 h,NaCl电解质质量浓度为1 g/L。结果表明,在此参数下出水COD水质指标稳定,并能达到国家《工业循环冷却水处理设计规范》(GB 50050—2007)标准。  相似文献   
735.
本文通过对美国四轮ATV强制性安全标准ANSI/SVIA 1-2010与ANSI/SVIA 1-2007的分析研究,阐述了2010版标准中许多修改内容是对2007版标准编辑性的修改,其目的是改善标准清晰度和一致性;实质性修改主要包括8项,其目的主要是适应安全性要求。同时也提出我国ATV产品在设计、配置和性能等方面面临的技术壁垒和安全技术改进方向,这对我国ATV产品出口美国和制定国家、行业标准具有重要指导意义。  相似文献   
736.
陈南 《火灾科学》2012,21(1):45-50
基于FDS对某酒吧特大火灾事故进行数值重构研究,再现了火灾发生、发展的全过程,并与火灾现场勘查报告、现场照片比对;与此同时,详细地分析和研究了火场中典型部位的温度、CO浓度及FED指数等细节性参数的发展变化趋势,结果表明,模拟中的火灾蔓延过程、烟气填充过程、热释放速率、温度等参数与火灾现场勘查笔录和电子物证基本吻合,可与火灾调查其它证据相佐证,完善火灾调查结论,为进一步研究和改善此类场所的防火措施和灭火救援方案提供了依据。  相似文献   
737.
李楠 《林业劳动安全》2012,25(3):6-8,27
欧债危机下会计集中核算对金融市场发展会产生一定的影响,当前的会计核算是以统一核算为基本手段,对资金进行集中控制。农村金融发展过程中受到会计集中核算制度的影响越来越大,通过加强财政资金支持,实现会计集中核算的整体目标。欧债危机下农村金融市场需要提升管理水平,才能更好的维持农村金融稳定,保证农村金融能够更好的服务"三农",从根本上提升农村金融的核心竞争力。  相似文献   
738.
For cetaceans, population structure is traditionally determined by molecular genetics or photographically identified individuals. Acoustic data, however, has provided information on movement and population structure with less effort and cost than traditional methods in an array of taxa. Male humpback whales (Megaptera novaeangliae) produce a continually evolving vocal sexual display, or song, that is similar among all males in a population. The rapid cultural transmission (the transfer of information or behavior between conspecifics through social learning) of different versions of this display between distinct but interconnected populations in the western and central South Pacific region presents a unique way to investigate population structure based on the movement dynamics of a song (acoustic) display. Using 11 years of data, we investigated an acoustically based population structure for the region by comparing stereotyped song sequences among populations and years. We used the Levenshtein distance technique to group previously defined populations into (vocally based) clusters based on the overall similarity of their song display in space and time. We identified the following distinct vocal clusters: western cluster, 1 population off eastern Australia; central cluster, populations around New Caledonia, Tonga, and American Samoa; and eastern region, either a single cluster or 2 clusters, one around the Cook Islands and the other off French Polynesia. These results are consistent with the hypothesis that each breeding aggregation represents a distinct population (each occupied a single, terminal node) in a metapopulation, similar to the current understanding of population structure based on genetic and photo‐identification studies. However, the central vocal cluster had higher levels of song‐sharing among populations than the other clusters, indicating that levels of vocal connectivity varied within the region. Our results demonstrate the utility and value of using culturally transmitted vocal patterns as a way of defining connectivity to infer population structure. We suggest vocal patterns be incorporated by the International Whaling Commission in conjunction with traditional methods in the assessment of structure.  相似文献   
739.
Environmental Science and Pollution Research - This paper examined the eutrophication literatures from 1998 to 2015 using bibliometric techniques basing on the database of Science Citation Index....  相似文献   
740.
特种设备在印染行业的广泛应用带来经济效益的同时也伴随着事故和风险,政府部门一直探寻有效的风险管理手段。近年来,保险作为转移风险的有效方式在安全生产方面备受关注,然而其在印染行业的特种设备中的应用还不够成熟。因此,文章根据印染行业特种设备的风险特点,着重从人、机、环、管四个方面分析其风险,并运用作业危险性评价法(LEC)评估作业人员的风险等级、计算事故最大可能损失(MPL)、运用等级系数安全评价法评估企业的安全性,从而量化印染企业的责任风险,应用于责任保险的保费费率浮动计算中。  相似文献   
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